RFC # 822
Obsoletes: RFC #733 (NIC #41952)
STANDARD FOR THE FORMAT OF
ARPA INTERNET TEXT MESSAGES
August 13, 1982
Revised by
David H. Crocker
Dept. of Electrical Engineering
University of Delaware, Newark, DE 19711
Network: DCrocker @ UDel-Relay
Standard for ARPA Internet Text Messages
TABLE OF CONTENTS
PREFACE .................................................... ii
1. INTRODUCTION ........................................... 1
1.1. Scope ............................................ 1
1.2. Communication Framework .......................... 2
2. NOTATIONAL CONVENTIONS ................................. 3
3. LEXICAL ANALYSIS OF MESSAGES ........................... 5
3.1. General Description .............................. 5
3.2. Header Field Definitions ......................... 9
3.3. Lexical Tokens ................................... 10
3.4. Clarifications ................................... 11
4. MESSAGE SPECIFICATION .................................. 17
4.1. Syntax ........................................... 17
4.2. Forwarding ....................................... 19
4.3. Trace Fields ..................................... 20
4.4. Originator Fields ................................ 21
4.5. Receiver Fields .................................. 23
4.6. Reference Fields ................................. 23
4.7. Other Fields ..................................... 24
5. DATE AND TIME SPECIFICATION ............................ 26
5.1. Syntax ........................................... 26
5.2. Semantics ........................................ 26
6. ADDRESS SPECIFICATION .................................. 27
6.1. Syntax ........................................... 27
6.2. Semantics ........................................ 27
6.3. Reserved Address ................................. 33
7. BIBLIOGRAPHY ........................................... 34
APPENDIX
A. EXAMPLES ............................................... 36
B. SIMPLE FIELD PARSING ................................... 40
C. DIFFERENCES FROM RFC #733 .............................. 41
D. ALPHABETICAL LISTING OF SYNTAX RULES ................... 44
August 13, 1982 - i - RFC #822
Standard for ARPA Internet Text Messages
PREFACE
By 1977, the Arpanet employed several informal standards for
the text messages (mail) sent among its host computers. It was
felt necessary to codify these practices and provide for those
features that seemed imminent. The result of that effort was
Request for Comments (RFC) #733, "Standard for the Format of ARPA
Network Text Message", by Crocker, Vittal, Pogran, and Henderson.
The specification attempted to avoid major changes in existing
software, while permitting several new features.
This document revises the specifications in RFC #733, in
order to serve the needs of the larger and more complex ARPA
Internet. Some of RFC #733's features failed to gain adequate
acceptance. In order to simplify the standard and the software
that follows it, these features have been removed. A different
addressing scheme is used, to handle the case of inter-network
mail; and the concept of re-transmission has been introduced.
This specification is intended for use in the ARPA Internet.
However, an attempt has been made to free it of any dependence on
that environment, so that it can be applied to other network text
message systems.
The specification of RFC #733 took place over the course of
one year, using the ARPANET mail environment, itself, to provide
an on-going forum for discussing the capabilities to be included.
More than twenty individuals, from across the country, partici-
pated in the original discussion. The development of this
revised specification has, similarly, utilized network mail-based
group discussion. Both specification efforts greatly benefited
from the comments and ideas of the participants.
The syntax of the standard, in RFC #733, was originally
specified in the Backus-Naur Form (BNF) meta-language. Ken L.
Harrenstien, of SRI International, was responsible for re-coding
the BNF into an augmented BNF that makes the representation